The Project has the following Aims: Aim 1) Develop a nanoliter liquid injection and movement system. We will construct and test components for a robust injection and movement system that can handle multiple liquid samples in the volume range of 10 to 500 nl. Our successful injection and movement systems for single and binary drop systems will be modified and assembled into multiple-sample liquid handling procedures. On-chip valving systems will be refined. Aim 2) Develop multiple independent reaction chambers. We will construct and test reaction chambers for optimal surface interactions, temperature profiles, and thermal cross talk between reaction chamber components. We will refine the reactors to produce high quality DNA genotyping and sequencing data. Aim 3) Demonstrate high-resolution separations. We will improve our current microscale gel electrophoresis system to equal the quality of conventional DNA sequencing devices. Optimization of gel channel configuration and surfaces will be performed. Additional effort will examine gel electrophoresis matrix modifications and polymerization. Aim 4) Optimize high sensitivity on-chip fluorescence detection. We will construct high sensitivity detectors capable of detecting both genotyping and sequencing reaction products. We will continue to improve the detectors by adjusting the doping concentrations and the shape of the implants. Alternate excitation strategies will also be investigated.